This is a hat designed for a Raspberry Pi Zero. It consists of two headers for I2S microphones (the sort of which are availble for under 2$ on aliexpress) and two level shifted outputs.
The primary purpose is to control 4-wire LED strips using the four pin header. This should also be able to provide the Pi Zero with power.
There's also a HUB-75 connector for driving LED panels. This might be less useful, and probably wasn't neccessary. (These are much better suited to be driven off a PI 3 or 4 if the frame rate or color depth matters, and some research into hzeller's excellent library points out that the I2S CLK pin is also the same as the PWM pin which drives the OE signal to the panels for better performance. I'm using a different pin mapping anyway (TODO: write it down..) so it wont work out of the box in any case.)